Molded insulation article



Dec. 9, 1930. w. c. TREGONING 1,734,557

MOLDED INSULATION ARTICLE Filed July 18-. 1929 IN VEN TOR.

A TTORNEY Patented ma. 9, 1930 vans STATES ATENT OFFI wltmani. c.rnneonme, or wauwarosa, wrsconsm, assrdzvrdia ITO CUTLER-HAM- man, me,or MILWAUKEE, WISCONSIN, A CORPORATION or DELAWARE IdOLDEI) IN S ULATIONARTICLE Application filed my 18,

to improvements in lamp socket casings com- 5 prising separableinsulating cap and body members of the character disclosedin mycopending application filed May 7 1928, Serial No. 275,7 68.

An object of the invention is to provide improved means for effectinginterlocking engagement anddisengagement of the insulating cap and bodymembers with respect to each other- Another and more specific object isto provide means for insuring against excessive bending of a portion ofthe insulating casing during assembly or dis-assembly of the cap andbody members whereby accidental breakage of the casing is avoided.

Another object is toprovide an insulating casing section having abendable wall portion of normal thickness or strength.

Another object is to provide a lamp socket base having means toaccommodate said wall portion upon inward bending thereof.

Other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate an embodiment of the inventionwhich will now be described, it being understood that the invention issusceptible of embodiment in other forms without departing from thescope of'the appended claims.

In the drawings. Figure 1 is a perspective View of the molded insulatingcap and body members of a lamp socket casing constructed in accordancewith my invention, the parts being shown in separated relation.

Fig. 2 is an enlarged top. plan view of the body member with a lampsocket base in position, the bendable portion of the wall being shown innormal position.

Fig. 3 is asimilar view, with the bendable portion of the wall indepressed relation.

Fig. 4 is a view similar to Fig. 3 showing the cap and body members inpartly assembled relation, the cap member being shown in section.

Fig. 5 is a fragmentary perspective view showing the inner surf-are ofthe wall of the application aforementioned.

1929. Serial No. 379,225.

body member and the bendable portion thereof.

Fig. 6 is an enlarged fragmentary sectional view on the line 6-6 of Fig.1, and

Fig. 7 is a top )lan view of a modified form of body mem er. I

Referring to the drawings. the numeral 10 designates in general a moldedinsulating cap of substantially the form shown ,in my Thus the capcomprises an intermediate bell-shaped portion 11, an interior'lythreaded bushing 12 integral therewith, and an integral lower orskirt-portion 13. The inner surface of portion 13 is provided with amultiplicity of equally spaced L-shaped or bayonet grooves, each slotincluding a horizontal arm 14 and a slightly deeper vertical arm 15. v The skirt portion 13 is preferably provided ,with radial projections 16alined with the respective arms 15 of the grooves to retain a properthickness of the insulation wall. ,Similarly the portion 13 ispreferably provided at the lower edge thereof and between theprojections 16 with relatively narrow annularlyarranged projections li'to strengthen said edge and to improve the appearance of the cap. 7

Cap 11 is further provided with an interior annular shoulder 18 againstwhich the upper end of the body portion of the casing is adapted to abutwhen the parts are assembled, as hereinafter described. A plurality ofintegral inward projections are provided within the bell shaped portion11 slightly above the shoulder 18, one of said projections being shownat 19,-the horizontal faces 19" of said projections being adapted tooverlie the top button or base 20 (Figs. 2 and 3) to insure againstupward displacement of the lamp socket when the parts thereof areassembled within the casing. The side edges of said projections arelikewise adapted for-cooperative engagement by a suitable wrench or thelike for effecting rotation of the cap in fitting the latter to athreaded pipe end, which feature is particularly desirable when the capis to be mounted within a husk or shade holder.

The body member 21 of the casing is also in certain respectssubstantially like that shown in my application aforementioned, and1ncludes a multiplicity of equally spaced integral radialprojections 22having their upper edges flush with the upper edge 23 of the bodymember. As shown, five of such projections 22 are provided, but ifdesired a sixth projection might be provided, as illustrated in dottedlines at 22 in Fig. 3. viously the number bayonet grooves 14, decreasedas desired,-provided that a cooperative relationship between the numberand spacing of the grooves and projections 15 maintained.

The projections 22 may be provided with slightly inclined surfaces 24 atthe forward sides thereof with reference to the direction of rotationthereof during assembl with the cap,-such surfaces being preferab e torightangled surfaces or shoulders for purposes of molding the bodymember, whereas the same likewise facilitate entry of said projectionsinto the relatively shallow arms 14 of the bayonet grooves to avoidWearing or chippin of the insulating shoulders during assem 1y of thecasing parts.

The additional projection 25 which is unequally spaced from theprojections 22 likewise preferably has its upper ed e flush with theupper edge of the body mem er, and the radial or right angular side edge26 thereof extends downwardly a distance which is preferably at leastasgreat as the length of the arms 15 of the bayonet grooves. The righthand side of projection 25 may if desired be inclined or beveled asindicated at 27, whereas the upper edge of said projection may beprovided with a slight radius or curvature, as best illustrated at 28 inFig. Formed integrally with the projection 25 1s a thumb piece oroperating button .29 having a ribbed or otherwise roughened surface 30,said button having a bevel or fillet 31 to increase the strength thereofand to facilitate molding.

As will be apparent from the drawings, the wall '32 (Fig. 6) of the bodymember is of equal thickness throughout the whole circumference thereof.As shown said wall is provided with a pair of slots 33, 34 arranged onopposite sides of the projection 25 and extending from the upper edge ofthe body member to points adjacent to the interior horizontal shoulder21 (Figs. 5 and 6) Also it will be noted that the slots 33, 34 arenonradial with respect to the longitudinal center of the body member 21,and said slots are further arranged-to diverge outwardly with respect toeach other from the inner surface of the body wall.

The slots 33, 34 thus form a tongue or portion 21 which is integral withthe wall of the body member but flexible with respect thereto. Moreover,since the upper end of Ob-- of pro ections 22 and v 15 may be increasedor portion 21 is r hiiired to move inwardly an appreciable distance withthe lower ends 33, 34 of the slots 33, 34 as an approximate center ofmovement, it is obvious that such lower ends of the slots may beextremely narrow, whereas the upper ends 33', 34* of said slots aresufficiently wide to provide for the required degree of inward movementof tongue 21 and projection 25 carried thereby.

Thus, as illustrated in Figs. 3 and 4 the tongue 21 when pressedinwardly is adapted to carry the projection 25 inwardly to a pointsubstantially flush with the normal circumference of the body member 21.Thereupon the body member 21 may be freely telescoped into the cap 10with projections 22 on the former engaging arms 15 of the bayonetgrooves in the latter. Then b simply rotating the body member in a clocwise direction with respect to the cap the projec tions 22 enter thearms 14 of the respective bayonet grooves to hold the parts againstendwise movement with respect to each other, while at the same time theside edge 26 of projection 25 snaps into engagement with a full depthshoulder 15 of an arm 15 of one of the bayonet grooves, as bestillustrated in Fig. 4.

When the casing hereindescribed is intended to enclose a keyless lampsocket, the wall of the body member will be uninterrupted with theexception of the slots 33, 34. When a key socket or pull chain socket isto be enclosed within the casing the body member 21 may be notched, asindicated at 35 in the drawings,it being noted that the notch 35 iscircumferentially spaced a considerable distance from the slots 33, 34to avoid unnecessary weakening of the casing walL.

Similarly when the body member is provided with plural notches (notshown) to accomodate a push button socket, the angular position of saidnotches with respect to slots 33, 34 will be properly selected.

As will be apparent to those skilled in the art, a body member 21 of thecharacter illustrated in Figs. 1 to 6 may be initially molded to serveas a keyless lamp socket, as

shown in Fig. 7 ,said body member having a relatively thin wall portion36 conforming to the desired shape of the notch 35. Said wall portion136 may then, if desired, be sheared or knocked out to adapt. the bodymember for use in conjunction with a pull chain or key type socket.Similar thin wall portions or knock-outs may be provided to adapt thebody portion of the casing for reception of a socket of the push buttontype.

The body member 21 is provided at the lower end thereof with a thread 37which may be formed thereon by the molding operation.

The insulating material of which the body member is formed isofsubstantiallv rigid but slightly flexible character, such, forinstance, as the phenol-formaldehyde conden-' What Iclaim as new anddesire to secured by Letters Patent is:

1. As an article of manufacture, a hollow casing comprising separablebody and cap members at least one of said members being formed ofsubstantially rigid but slightly flexible insulating material, one ofsaid members having a multiplicity of equally spaced bayonet groovesformed therein, the other member having a multiplicity of equally spacedintegral insulating projections adapted for cooperative engagement withsaid bayonet grooves, said last mentioned member having an additionalinsulating projection unequally spaced from said first mentionedprojections, said member havin a slot on each side of said additionalpro ection, and said slots being non-radial with respect to thelongitudinal center of said member and outwardly divergent with respectto each other whereby the walls of said slots cooperate to limit inwardmovement of said additional projection, for the purpose set forth.

2. As an article of manufacture, a hollow casing comprising separablebody and cap members each formed of substantially rigid but slightlyflexible insulating material, one of said insulating members having amultiplicity of equally spaced bayonet grooves formed therein, the otherinsulating memher having a circumferential wall of substantially uniformthickness and a multiplicity of equally spaced projections substantiallyflush with the upper edge thereof adapted for cooperative engagementwith said bayonet grooves, said last mentioned member having anadditional projection unequally spaced from said first mentionedprojections said member having slots in the wall thereof on each side ofsaid additional projection, said slots being non-radical with respect tothe longitudinal center of said member and outwardly divergent withrespect to each other whereby the sides of said slots cooperate to limitinward bending of the wall portion therebetween, and a lamp socket basewithin the casing, said base having means to accommodate theaforementioned wall portion upon inward bending of the latter.

- 3. As an article of manufacture, a hollow casing comprising separablebody and cap members each formed of substantially rigid but slightlyflexible insulating material, one of said insulating members having amultiplicity of equally spaced bayonetgrooves formed therein, the otherinsulating member having a circumferential wall of substantia-llyuniform thickness and 'a multiplicity of equally spaced projectionssubstantially .flush with the upper edge thereof adapted for cooperativeengagement with said bayonet grooves, said last mentioned member havingan additional and relatively longerprojection unequally spaced from saidfirst mentioned projections, said member having slots in the wall.thereof on each side of said additional projection, said slots beingnon-radial with respect to the longitudinal center of said member andoutwardly divergent with respect to each other whereby the sides of saidslots cooperate to limit-inward bending of the wall portionthcrebetween, a lamp socket base within the casing, said base hav ingmeans to accommodate the aforementioned wall portion upon inward bendingof the latter, vand said Wall having a notch therein to'accommodate aswitch actuating element, said not-ch being circumierentially spacedfrom said slots to avoid substantal wezlilkening of the intermediateportions of the wa An electric lamp socket casing comprising separatelymolder cap and body members of insulating material, said cap memberhaving a plurallty of bayonet grooves formed in the wall thereof, saidbody member having a plurality of projections integral therewith andadapted to register with said grooves in substantially any rotaryrelation of said members, the wall of said body member having a pair ofadjacentslots which diverge outwardly with respect to each other fromthe inner surface of said wall, an additional projection carried by saidbody member between said slot-s, said projections cooperating jointlywith said bayonet grooves to lock said cap and body members againstrelative re tarV and longitudinal movements. and the we ls of said slotsserving to limit the inward flexure of that portion of the body memberlocated .therebetween.

5. An electric lamp socket casing comprising separatcly molded cap andbody members of insulating material, said cap member having a pluralityof bayonet grooves formed in the inner wall tlu-rm'i'i.v a

said body member having a plurality of prm jections integral therewithand adapted to register with said grooves in substantially any rotaryrelation of said men'lbers, the wall of said body member having a pairof spaced. substantially vertical slots extending from the upper edgethereof, said slots diverging outwardly with respect to each other fromthe inner surface of said wall and the walls of each slot divergingslightly from the lower ends thereof. an additional projection carriedby said body member between said slots, said projections cooperatingjointly with said bayonet grooves to lock said cap and body membersagainst l ti rotary and gtudinal movements and the wallsot saiddiverging slots serving to limit the inward flexure of that portion ofthe'bo'dy member located'therebetween; f is 6.'In an electric lampsocket-casing, in"

combination, a molded hollow body member portion, and an additionalradial projectionon said portion adjacent to said slot, said lastmentioned projection being unequally;

spaced from said first mentioned projecti ms.. 7 .In an electric lampsocket casing, in comb nation, a molded'hollow body member of insulatingmaterial, said body memher having a plurality of integralradialprojections substantially flush with t'heupper edge thereof andequally spaced from each other, said body member having a pair ofcircumferentially spaced slots or passages extending substantiallyvertically from the upper edge thereof to provide for flexure of thewallportion located therebetween., said, slots diverging outwardly withrespect to each other from the inner surface of said body member and theopposed walls of said slots coacting to limit inward fiexure of said"portion of the body member, and an additional radial 1 projection onsaid flexible portion,-

- saidlast mentioned projection being unequa'l- 1y spacedfrom saidfirstmentioned projections. 4 8 An electric lamp socket or the likecomprising a casing having independent cap and body members formed ofsubstantially rigid but slightly flexible insulating material, and

substantially L-shaped notches in the inner said body member having aplurality of equally spaced integral lateral rojections ad acent tothe'upper edge thereo said projections being adapted to jointly registerwith a corresponding group of notches in said cap member whereby saidmembers may be joined by sequential telescopic movement and partialrelative rotation thereof, said wall'thereof, the open ends'ofsaidnotches "beingflush wlth the lower edge of said cap,

body member having a non-radial slot extending downwardly from the upperedge thereofto provide for flexure of a portion of the body memberadjacent thereto, the walls of said slot coacting to limit the iuwardflexure of said portion, and another lat-- cra-lprojection onsaidflexible portion unequally spaced from said first mentioned proectionsand adapted upon such relative rotation of saidmembers to snap 1ntoengagement with a shoulder of one of said notches whereby said membersare positively locked against relative rotary or longitudinal movements.v 1 a In witness whereof, I have hereunto subscribed my name,

WILLIAM C. TREGONING.

latching means for securing said members together in substantially anyrelat-ive rotary position thereof and serving to hold the' same togetheragainst endwise separation and relative rotary displacement, sa dlatching means comprising shouldered insulating portions integral withthe respective cap and body members and adapted for positiveinterlocking engagement with each other, a shouldered portion on one ofsaid members being formed to require yielding movementthereof foreffecting such interlocking en-. gagement, said last mentioned memberhaving a pair of slots through the wall thereof on opposite sides ofsaid shouldered portion, and'said slots being outwardly divergent withrespect to each other to positively limit inward bending of the tongueformed thereby. j

9. A locking joint for insulating members consisting of a hollowinsulating body memher and an insulating cap member, said cap memberhaving a plurality of equally spaced

